In a digital communication system a receiver can provide side information in addition to the demodulated data. The side information, if it represents a reliability measure of the decoded symbol, can be used in an error control decoder to increase the coding gain and reduce bit error rate (BER) in a radio frequency (RF) environment. Since the side information accompanies each demodulated channel symbol, it is often called the channel symbol reliability weight.
Depending upon the type of modulation and demodulation techniques being used, the side information can be generated in different ways. The way in which the side information is generated and applied to the error control process can have a substantial influence on its success in reducing BER.
Thus, what is needed is a method and apparatus that can generate and apply the side information for reducing BER. Preferably, the side information will be generated and applied in a manner that produces the greatest possible improvement in receiver performance.